Effects of coal bedding dip angle on hydraulic fracturing crack propagation

Abstract As a commonly used and effective technology for increasing the permeability of coal–rock reservoirs, hydraulic fracturing has been widely in engineering sites to realize efficient exploitation utilization gas resources reservoirs. The core is initiation, propagation, path cracks. In this paper, combination true triaxial physical test numerical simulation study influence coal bedding characteristics on crack propagation discuss important role formation. Results show that control effect dip angle under same stress conditions stronger than maximum principal stress, weaker angles 0° 90°. Reasonable fluid displacement setting conducive formation complex fracture network structure, small opening primary natural fractures, large cracks pass through structural surface interface. Global local methods finite element mesh embedding zero-thickness cohesion pore-pressure node merging method simulate are established using Python language ABAQUS analysis platform, respectively. results suggest main fractures formed along direction, secondary branch direction condition wherein 30°. Under different fields discharges, controlling closely related parameters.